The duality conjecture for $C^A$-free gammoids

A $C^A$-free gammoid is a gammoid avoiding the excluded configuration $C^A$. The duality conjecture. The class of $C^A$-free gammoids is closed under duality. This is presented as an expected strengthening of the result that every $R^A$-free strict gammoid is dual to a gammoid; the supplied status evidence marks it as open.